This invention relates to treating fluid matter and particularly, but not exclusively, to heating gaseous matter.
EP-B-68853 discloses moving a bed of particulate material in a band continuously along an annular path by passing a fluid medium provided as combustion gases having both circumferential and vertical components through the bed along its path. The combustion gases heat the particulate material as they pass through the bed, and matter, which may be other particulate material, is added to the bed so as to mix with the heated particulate matter and be heated thereby.
An object of the present invention is to utilise a bed of particulate material which moves in a band along an annular path as aforesaid for treating fluid matter.